Diet–vaccine interactions: SQM Iron and Salmonella vaccination shape poultry gut microbiota

Globally, non-typhoidal Salmonella (NTS) is a persistent food safety challenge and pre-harvest control is an industry priority. While Salmonella vaccines are rapidly gaining adoption, their interactions with other common management practices such as nutritional strategies remain unclear. Iron metabolism is particularly important, as it influences host immunity, pathogen colonization, and shapes the gut microbiome. This study investigates how live-attenuated Salmonella vaccine (AviPro Megan Vac 1) and iron-based nutritional management interact to shape the cecal microbiota of broiler chickens. Specifically, we focus on SQM Iron, with a complexation process that enables time- and tissue-specific release of this critical nutrient. Our findings indicate that targeted combinations of immune stimulation and micronutrient supplementation can selectively remodel the poultry gut microbiome, with potential implications for nutrient utilization, microbial metabolism, and integrated, non-antibiotic approaches to reduce Salmonella burden while supporting flock health.